Assuming there is no conflict between the club 'brand/image' and the advertisers 'brand/image then I would assume the deal is done mostly on what is the greatest financial reward for the club?
I understand the benefits of being linked with top global brands in advertising but it strikes me that this is a similar discussion to team building - we know where we are now and where we want to be. However, it's not one step it's several and we need to work towards getting to the top and then the global brands will be knocking on our door.
With regards to Sportpesa being well known -was Etihad before Man City spent the money?